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A/C Compressor Clutch can cause loss of car control?

1998 Chevy Cavalier

131,000 miles



Car makes a slight metallic sound with A/C off (sounds like a very quiet school bell or as if you put a marble in a metal bowl that is slightly vibrating. The sound is most evident when I am next to walls or other cars, as it bounces back to me in the car). This started after a few weeks of not driving or starting the engine.



The dealer tells me my A/C Compressor Clutch is “coming apart” what does this mean?



Can the clutch come apart and present a safety hazard (serpentine belt runs everything on a '98 Cavalier, I believe)? Why?



Why would this be a cause of the metallic sound I am hearing?



What’s the worst that can happen here?

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The dealer says a leaking water pump and missing pulley bolt is also one reason I am hearing the metallic sound (which disappears or lessens sometimes). Any thoughts on this?



What’s the worst that can happen here?



Cost to replace:



*Compressor clutch: $720 with labor

*Water pump and pulley bolt: $350

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I’m getting a second opinion tomorrow.

Oh, and I have not run the Air Conditioning for years. It stopped working that long ago. So this sound occurs even without the A/C, fans (or defogger) on.

Most likely the compressor clutch bearing is failing. When this happens it allows the compressor clutch pulley to tilt slightly coming in contact with the compressor clutch plate. Because of the shape of the pulley it can cause it to ring like a bell.

If you haven’t operated the AC system for years, it’s highly doubtful that there’s still a refrigerant charge in the system. So the AC won’t function. If that’s the case, why replace the compressor clutch? I believe your vehicle was available without AC. If that’s the case, I’d just install a serpentine belt for a Cavalier that came without AC. That would be a whole lot cheaper.

Tester

Anywhere I can find an easy-to-understand diagram of my engine? I’d feel better talking to the mechanic if I understand what is what.

Also, isn’t replacing the bearing an option as well? That might cause the A/C to work if recharged, no?

Didn’t operate the A/C because of an apparent leak.

What I’m concerned with is the compressor clutch falling into the belt and causing a loss of steering control. Possible?

Well, what can happen is, if the clutch pulley tilts far enough it can allow the serpentine belt to walk off the pulley. You then lose power steering assist because the power steering pump is no longer turning.

If the AC system had a leak years ago, the entire AC system is going to need to be rebuilt. During these years, air and moisture have contaminated the AC system. So it’s not just a matter of recharging the AC system with refrigerant. That’s why I recommended installing a belt for a Cavalier without AC.

Tester

Right. I’m willing to go without AC. I had a second shop – Midas – take a look, and they recommended a new compressor, which equals a few other parts.

All this for over $1,000, which seems to be the competitive rate around here. The car I doubt is worth that much.

But another highly-recommended mechanic in the area just told me he can install with a bypass pulley for $300-400. That’s what we’re going with, because we need the car and are not in a position to buy. Oh, how I wish I could buy! The peace-of-mind would be incredible! lol

Thanks for the tip. I think it will save me hundreds of dollars!